Gerardo Perillo - Academia.edu (original) (raw)

Papers by Gerardo Perillo

Pure and Applied Chemistry, 2018

Lakes, rivers, estuaries and ocean waters control many important natural functions at the regiona... more Lakes, rivers, estuaries and ocean waters control many important natural functions at the regional-global level. Hence, integrative and frequent long-term water monitoring is required globally. This paper describes the main features and innovations of a low-cost monitoring buoys network (MBN) deployed in a temperate region of Argentina. The MBN was designed to record extended time series at high-frequency, which is of great value for the scientific community, as well as for decision-makers. In addition, two innovative designs belonging to two versions of moored buoys (i.e. shallow waters and coastal marine waters) were presented. It was shown that the cost of either of two versions of the buoy is low, which can be considered as the main advantage.

Existe un gran diversidad de nombres y clasificaciones de formas de fondo en todos los idiomas, 1... more Existe un gran diversidad de nombres y clasificaciones de formas de fondo en todos los idiomas, 10 que redunda en complicaciones ala hora de describirlas. Nuestro idioma no es una excepcion y por 10 tanto es tiempo de establecer un esquema que reuna una nomenclatura y clasificacion de formas de fondo. El objetivo del presente trabajo es dar una primera aproximacion hacia ese logro para formas de fondo, princi- palmente transversales al flujo. Estos flujos se consideran tanto unidireccionales (en senti do amplio) y oscilatorios. Se presenta tambien una breve resefia de las relaciones dinamicas entre el flujo y el sedimento necesario para comprender el porque de estas formas. Pero no se incluyen las estructuras primarias generadas por las mismas. Entre otros aspectos, se prop one el empleo del termino "dunas" unicamente para las formas transversales generadas por flujos de agua, y del termino "medano" cuando el agente es el viento.As it is common in many languages,...

Ocean & Coastal Management, 2021

With the increasing need for and emergence of research on ocean and coastal issues in the context... more With the increasing need for and emergence of research on ocean and coastal issues in the context of the COVID-19 pandemic, the Ocean & Coastal Management journal presents this Special Issue with relevant articles within the scope of Coastal Management in times of COVID-19. This Special Issue received 43 tentative abstracts, 29 manuscripts were submitted, and finally, 12 articles were accepted. We provide a wide panorama of those twelve articles that integrate the special issue, covering a diverse range of topics regarding coastal management in the COVID-19 pandemic. Seven papers are studies that discuss environmental and social problems during this time in coastal zones, while the other five explore the use of technology to face COVID-19 on beaches. These twelve articles give some insights to improve coastal management, focused on tourist beaches, natural disasters, and fisheries. In sum, this special issue offers an organized compendium of high-level articles, as a contribution to evolve towards the better ocean and coastal management, within the rapid emerging of publications about COVID-19.

Se presentan resultados hidráulicos y sedimentológicos de una campaña al arroyo Naposta Grande. A... more Se presentan resultados hidráulicos y sedimentológicos de una campaña al arroyo Naposta Grande. A pesar que existe un gran número de obras hidráulicas sobre el curso inferior del arroyo, no existen aún datos publicados acerca del caudal sólido transportados por el mismo. Se ubicó una sección de aforo adecuada, sobre la cual se determinó la batimetrÌa del área. Se midieron las velocidades en verticales separadas 0.5 m en toda la sección y a partir de estos valores se determinaron las curvas de igual velocidad en la sección con las que se calculó el caudal y la distribución de los esfuerzos de corte del fondo. Se obtuvieron muestras del sedimento transportado como carga de fondo por medio de trampas, verificándose transporte diferentes en cada faja. Paralelamente se calculó el transporte como carga de fondo por medio de cuatro diferentes ecuaciones y se comparó con los valores medidos, determinándose cual de las ecuaciones predijo mejor el valor del transporte. De las muestras de sedi...

Journal of South American Earth Sciences, 2018

This work aims to assess how Pleistocene glaciations modeled the landscape in the upper Senguer R... more This work aims to assess how Pleistocene glaciations modeled the landscape in the upper Senguer River basin and its relationship to current watershed features (drainage surface and fluvial hydrological regime). During the Pleistocene six glacial lobes developed in the upper basin of the Senguer River localized east of the Andean range in southern Argentinean Patagonia between 43º 36'-46º 27' S. To describe the topography and hydrology, map the geomorphology, and propose an evolution of the study area during the Pleistocene we employed multitemporal Landsat images, national geological sheets and a mosaic of the digital elevation model (Shuttle Radar Topography Mission) along with fieldwork. The main conclusion is that until the Middle Pleistocene, the drainage divide of the Senguer River basin was located to the west of its current limits and its rivers drained the meltwater of the glaciers during interglacial periods. However, processes of drainage inversion and drainage surface reduction occurred in the headwater of most rivers of the basin during the Late Pleistocene. Those processes were favored by a relative shorter glacial extension during LGM and the dam effect produced by the moraines of the Post GPG I and III glaciations. Thus, since the Late Pleistocene, the headwaters of several rivers in the basin have been reduced, and the moraines corresponding to the Middle Pleistocene glaciations currently divide the watersheds that drain towards the Senguer River from those that flow west towards the Pacific Ocean.

Ocean & Coastal Management, 2016

Abstract Coastal environments are spaces where people may develop varied economic and recreationa... more Abstract Coastal environments are spaces where people may develop varied economic and recreational activities, such as tourism, which usually damage beaches and other natural resources commonly placed in these settings. The aim of this paper is to present a methodology to estimate and evaluate the Beach Carrying Capacity (BCC) and the actual beach usage level in coastal cities, using on-site information and video processing to provide significant real-time data. To test our methodology, we chose the coastal city of Monte Hermoso, Argentina, as a pilot site because it is by far the prime choice for a large population during summer vacation in this country. Initially, to estimate BCC, cartographic information about facilities and beach zones was collected and combined with surveys requested to tourists, to better understand their habits and preferences. This allowed an accurate estimation of other beach capacities related to BCC. Secondly, beach video sequences were processed with an algorithm that identified, located and counted people on the beach with an adequate accuracy. The actual occupancy factor was computed and used to asses whether the BCC had been exceeded. Also, people were tracked and their preferred relaxing areas were registered (e.g, closer to seaside during the morning). Finally, all the information was stored and visualized using a Geographic Information System (GIS) which allows both to analyze the different information layers and to produce interactive thematic maps. In this way, the resulting methodology may help to identify zones under risk of deterioration and to define suitable places for the development of varied activities (specially those related to tourism). It may also serve as a dashboard for decision and policy making and contribute to coastal management planning as well.

Journal of the Marine Biological Association of the United Kingdom, 2011

We investigated the occurrence and seasonal variation of the biomass of rotifers, tintinnids, the... more We investigated the occurrence and seasonal variation of the biomass of rotifers, tintinnids, the heterotrophic dinoflagellate Gyrodinium fusus and copepod nauplii in the Bahía Blanca Estuary (38°42′S61°50 ′W), Argentina, during an annual cycle. The rotifers fauna comprised three species, while the tintinnids were represented by sixteen species. The biomass of the rotifers fluctuated between 0.62 and 8.90 µgC l−1. The biomass of the tintinnids fluctuated between 0.13 and 9.37 µgC l−1, the biomass of the nauplii stages between 1.78 and 7.65 µgC l−1; while the biomass of G. fusus varied from 0.26 and 7.94 µgC l−1, these results are compared to estimates of microzooplankton in other regions. We analysed the presence of the different groups in relation to the environmental variables, based on point-biserial correlation. Salinity fluctuated between 25.14 and 36.64; temperature between 7.5 and 23.2°C, solar radiation between 0.9 and 30.8 MJ m−2d−1 and Secchi distance between 0.25 and 1.43...

The aim of this work is to evaluate the applicability of the 3D model obtained through Structure-... more The aim of this work is to evaluate the applicability of the 3D model obtained through Structure-from-Motion (SFM) from unmanned aerial vehicle (UAV) imagery, in order to characterize bioerosion patterns (i.e., cavities for roosting and nesting) caused by burrowing parrots on a cliff in Bahía Blanca, Argentina. The combined use of SFM-UAV technology was successfully applied for the 3D point cloud model reconstruction. The local point density, obtained by means of a sphere of radius equal to 0.5 m, reached a mean value of 9749, allowing to build a high-resolution model (0.013 m) for resolving fine spatial details in topography. To test the model, we compared it with another point cloud dataset which was created using a low cost do-it-yourself terrestrial laser scanner; the results showed that our georeferenced model had a good accuracy. In addition, an innovative method for the detection of the bioerosion features was implemented, through the processing of data provided by SFM like color and spatial coordinates (particularly the y coordinate). From the 3D model, we also derived topographic calculations such as slope angle and surface roughness, to get associations between the surface topography and bioerosion features.

Frontiers in Ecology and Evolution, 2020

Coastal wetlands, such as saltmarshes and mangroves that fringe transitional waters, deliver impo... more Coastal wetlands, such as saltmarshes and mangroves that fringe transitional waters, deliver important ecosystem services that support human development. Coastal wetlands are complex social-ecological systems that occur at all latitudes, from polar regions to the tropics. This overview covers wetlands in five continents. The wetlands are of varying size, catchment size, human population and stages of economic development. Economic sectors and activities in and around the coastal wetlands and their catchments exert multiple, direct pressures. These pressures affect the state of the wetland environment, ecology and valuable ecosystem services. All the coastal wetlands were found to be affected in some ways, irrespective of the conservation status. The main economic sectors were agriculture, animal rearing including aquaculture, fisheries, tourism, urbanization, shipping, industrial development and mining. Specific human activities include land reclamation, damming, draining and water extraction, construction of ponds for aquaculture and salt extraction, construction of ports and marinas, dredging, discharge of effluents from urban and industrial areas and logging, in the case of mangroves, subsistence hunting and oil and gas extraction. The main pressures were loss of wetland habitat, changes in connectivity affecting hydrology and sedimentology, as well as contamination and pollution. These pressures lead to changes in environmental state, such as erosion, subsidence and hypoxia that threaten the sustainability of the wetlands. There are also changes in the state of the ecology, such as loss of saltmarsh plants and seagrasses, and mangrove trees, in tropical wetlands. Changes in the structure and function of the wetland ecosystems affect ecosystem

Marine and Freshwater Research, 2019

This study evaluated, for the first time, organic and metal contaminants in sediments from Argent... more This study evaluated, for the first time, organic and metal contaminants in sediments from Argentinean saline lakes, specifically La Salada shallow lake, a small polymictic lake on the south border of the Pampean region. The concentration of 16 priority polycyclic aromatic hydrocarbons (PAHs) and 8 metals (Cd, Cu, Cr, Fe, Mn, Ni, Pb and Zn) was assessed and the ecotoxicological effects of these pollutants were examined. The total concentration of the 16 PAHs ranged from 12.55 to 10679.48ngg–1 dry weight, with a predominance of four-ringed PAHs. Molecular ratio analysis showed pyrolytic sources as the main source of PAHs. Among the metals, Mn, Fe and Zn had the highest concentrations in sediments. General metal levels revealed a multiplicity of point sources and rock weathering as their main source. Regarding the potential ecotoxicological effects, adverse effects may be expected from PAHs because several compounds exceeded the sediment quality guidelines threshold effect level and l...

Inland Waters, 2018

ABSTRACT Multiple regressions, wavelet spectra, and Fourier spectra were employed to analyze fluc... more ABSTRACT Multiple regressions, wavelet spectra, and Fourier spectra were employed to analyze fluctuations in the surface areas of 2 Patagonian lakes during 1998–2015 and relate these to fluctuations in precipitation, evaporation, river discharge, and 2 southern climate modes, the Antarctic Oscillation (AAO) and El Niño Southern Oscillation, expressed in terms of the Southern Oscillation Index (SOI). Multiple regression analysis suggested that discharge was the primary driver of interannual lake area variations. Cross-spectrum analysis demonstrated a maximum significant correlation between river discharge and both AAO and SOI indices at annual and interannual timescales (2–3 yr). During 1998–2015, the annual discharge signal was related to both the AAO annual and every 2 year signals. When a strong La Niña (positive SOI) event occurred, however, river discharge was significantly reduced, resulting in a decrease in lake surface area.

Earth Science Informatics, 2016

In semi-arid environments there is often a lack of data on hydrological variables that limits the... more In semi-arid environments there is often a lack of data on hydrological variables that limits the ability to understand key hydrological processes. In response to this need, geomorphometric analysis is a quantitative approach that has proven to be useful. This work aims to assess and classify 35 exorheic drainage basins located in a semi-arid area of Argentina (Northeastern Patagonia) according to their geomorphometric properties by using GIS technology and principal component (PCA) and cluster analysis (CA) multivariate techniques. In addition, an assessment of automated drainage network extraction accuracy was performed by comparing it with the actual drainage network. The study showed that it was possible to derive automated drainage networks with errors lower than 6 %. By comparing both PCA and CA, it was found that the former allows a good understanding of the clustering of basins from the CA. All basins were clustered into four groups following a significant spatial continuity. This type of study gives the basis for regional-scale analysis, and provides further information for subsequent modeling.

Resumen. Se presentan resultados hidrAEulicos y sedimentolUgicos de una campaaea al arroyo Napost... more Resumen. Se presentan resultados hidrAEulicos y sedimentolUgicos de una campaaea al arroyo NapostAE Grande. A pesar que existe un gran nœmero de obras hidrAEulicas sobre el curso inferior del arroyo, no existen aœn datos publicados acerca del caudal sUlido transportados por el mismo. Se ubicU una secciUn de aforo adecuada, sobre la cual se determinU la batimetrIa del AErea. Se midieron las velocidades en verticales separadas 0.5 m en toda la secciUn y a partir de estos valores se determinaron las curvas de igual velocidad en la secciUn con las que se calculU el caudal y la distribuciUn de los esfuerzos de corte del fondo. Se obtuvieron muestras del sedimento transportado como carga de fondo por medio de trampas, verificAEndose transporte diferentes en cada faja. Paralelamente se calculU el transporte como carga de fondo por medio de cuatro diferentes ecuaciones y se comparU con los valores medidos, determinAEndose cual de las ecuaciones predijo mejor el valor del transporte. De las ...

Latin American journal of sedimentology and basin analysis, 2005

Instituto Argentino de Oceanografia, CC 804, B800FWB Bahia Blanca, Argentina Departamento de Geol... more Instituto Argentino de Oceanografia, CC 804, B800FWB Bahia Blanca, Argentina Departamento de Geologia, Universidad Nacional del Sur, San Juan 670, B8001ICN Bahia Blanca, Argentina E-mail: perillo@criba.edu.ar Starting with present issue, the new Latin American Journal of Sedimentology and Basin Analysis (LAJSBA) is born. This was announced by Matheos and Perillo (2204) as way to expand the future and to achieve a larger integration among the Latin American researchers. During the last 11 years, AAS Revista was the main way to express our scientific views but mostly concentrated in the work being done in Argentina. LAJSBA has arrived to provide a complete new spectrum of possibilities reaching also a much larger international community. However, we do not see LAJSBA as circumscribed to papers written by Latin American researchers but it is open to any specialist that would like to contribute to enhance our knowledge about Sedimentology and Basin Analysis.

Journal of Coastal Research, 1991

A general description of some dynamic characteristics of the Bahia Blanca estuary is presented. T... more A general description of some dynamic characteristics of the Bahia Blanca estuary is presented. The effects of the prevailing winds and the geometry of the Main Channel of the estuary over the tide are assessed. The NW and N winds produce large deviations both in height (up to 4 m) and time (up to 2 hs) from the predicted astronomical tide. The estuary is classified as hypersynchronous, where convergence is the dominant factor producing a marked headward increase in the tidal amplitude.

Geoacta, 2008

Data reconstruction of non stationary heterogenic fields obtained at the study area is a process ... more Data reconstruction of non stationary heterogenic fields obtained at the study area is a process intrinsic in coastal studies, for that is necessary to implement interpolation techniques that minimize the involved error. In general, a measured variable in coastal regions presents gaps in spatial or temporal information. These variables are involved under other processes that evaluate other variables and parameters. The results could be used to solve system of equations that could propagate significative errors which can be accumulated at the intervenient systems. The Objective Analysis is an interpolation procedure based in the Gauss-Markov mapping that can provide answers to these needs. Some authors had applied this method in meteorological and oceanographic fields, besides that is a good data-analysis tool and a basis for the design of observational arrays. In this work we propose to analyze an implementation of this interpolation technique based in the Objective analysis (or map...

Latin American journal of sedimentology and basin analysis, 2003